h1{
    width: 400px;
    height: 100px;
    padding: 50px;
    margin: 50px;
    border:1px solid gold;
}
span{
    width: 400px;
    height: 100px;
    padding: 10px;
    margin: 10px;
    border: 1px solid chartreuse;
}
/* div{
    display: inline;
}
a{
    display: block;
    width: 400px;
    height: 100px;
} */
a{
    display: inline-block;
    width: 200px;
    height: 100px;
    border:1px solid crimson;


}
a:hover{
    background-color: lawngreen;
    
}
div.box_before{
    width: 350px;
    height: 30px;
    background-color: turquoise;

}

div.box{
    /* 替代盒子模型 */
    /* box-sizing: border-box; */
    /* 宽度 */
    width: 350px;
    /* 高度 */
    height: 150px;
    /* 外边距 */
    margin: 25px;
    /* 内边距 */
    padding: 25px;
    /* 边框 */
    border:5px solid lawngreen;
}

div.box_after{
    width: 350px;
    height: 30px;
    background-color: turquoise;

}
div.box_outline{
    width: 500px;
    height: 300px;
    border: 2px solid brown;
}
div.box_size{
    width: 50%;
    min-width: 300px;
    height: auto;
    min-height: 100px;
    background-color: crimson;
}
div.box_margin{
    width: 300px;
    height: 100px;
    /* margin: 20px; */
    margin: 10px 20px 5px 5px;
    /* margin-top: 50px;
    margin-left: 30px; */
    /* margin: 0 auto;水平居中 */
    /* margin-bottom: 50px; */
    background-color: cyan;
}
div.box_margin2{
    width: 300px;
    height: 100px;
    margin-top: -50px;
    background-color: darkorchid;
}
div.box_outline p{
    margin-left: 30px;
    width: 100px;
    height: 30px;
    border-left: 1px solid brown;
    border-top: 2px solid brown;
    border-bottom: 3px solid brown;
    border-right: 4px solid brown;
    /* padding-left: 5px;
    padding-top: 2px; */
    padding: 2px 0 0 5px;

}
div.box_outline p:hover{
    border: 2px solid rgb(0, 255, 55);

}